package WordCount;
import Snowball.*;
import MailLogger.*;
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.util.Vector;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * This is an example Hadoop Map/Reduce application.
 * It reads the text input files, breaks each line into words
 * and counts them. The output is a locally sorted list of words and the
 * count of how often they occurred.
 *
 * To run: bin/hadoop jar build/hadoop-examples.jar wordcount
 *            [-m <i>maps</i>] [-r <i>reduces</i>] <i>in-dir</i> <i>out-dir</i>
 */
public class WordCount3 extends Configured implements Tool {

  /**
   * Counts the words in each line.
   * For each line of input, break the line into words and emit them as
   * (<b>word</b>, <b>1</b>).
   */
  /**
  word.set(validTerm);
  output.collect(word, one);
  reporter.setStatus((String)validTerms.get(j));
  **/
  public static class MapClass extends MapReduceBase
    implements Mapper<LongWritable, Text, Text, Text> {

    private Text text = new Text();
    private Text text2 = new Text();
    //private final static IntWritable one = new IntWritable(1);

    public void map(LongWritable key,
                    Text value,
                    OutputCollector<Text, Text> output,
                    Reporter reporter) throws IOException {
      String line = value.toString();

      StringTokenizer itr = new StringTokenizer(line,"\t");
      String termPair = itr.nextToken();
      String termFreq = itr.nextToken();
      if (termFreq.equals("1")) {
        return ;
      }

      StringTokenizer itr2 = new StringTokenizer(termPair,",");
      String term = itr2.nextToken();
      term = term.replace("\"","`");
      String associatedTerm = itr2.nextToken();
      associatedTerm = associatedTerm.replace("\"","`");
      associatedTerm = "\"" + associatedTerm + "\"";

      text.set(term);
      text2.set(associatedTerm+":"+termFreq);
      reporter.setStatus(term + " => " + associatedTerm+":"+termFreq);
      output.collect(text, text2);
    }
  }
  /**
   * A reducer class that just emits the sum of the input values.
   */
  public static class Reduce extends MapReduceBase
    implements Reducer<Text, Text, Text, Text> {

    private Text text = new Text();

    public void reduce(Text key,
                       Iterator<Text> values,
                       OutputCollector<Text, Text> output,
                       Reporter reporter) throws IOException {
      String termFreqPairs = "";
      String termFreqPair = "";
      while (values.hasNext()) {
        termFreqPair = ""+values.next();
        reporter.setStatus("add " + termFreqPair + " to " + key);
        termFreqPairs += termFreqPair + ",";
      }
      termFreqPairs = termFreqPairs.substring(0,termFreqPairs.length()-1);
      text.set(termFreqPairs);
      output.collect(key, text);
    }
  }

  static int printUsage() {
    System.out.println("WordCount3 [-m <maps>] [-r <reduces>] <input> <output>");
    ToolRunner.printGenericCommandUsage(System.out);
    return -1;
  }

  /**
   * The main driver for word count map/reduce program.
   * Invoke this method to submit the map/reduce job.
   * @throws IOException When there is communication problems with the
   *                     job tracker.
   */
  public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), WordCount3.class);
    conf.setJobName("WordCount3");

    conf.setOutputKeyClass(Text.class);
    conf.setOutputValueClass(Text.class);

    conf.setMapperClass(MapClass.class);
    conf.setCombinerClass(Reduce.class);
    conf.setReducerClass(Reduce.class);

    conf.setNumReduceTasks(1);

    List<String> other_args = new ArrayList<String>();
    for(int i=0; i < args.length; ++i) {
      try {
        if ("-m".equals(args[i])) {
          conf.setNumMapTasks(Integer.parseInt(args[++i]));
        } else if ("-r".equals(args[i])) {
          conf.setNumReduceTasks(Integer.parseInt(args[++i]));
        } else {
          other_args.add(args[i]);
        }
      } catch (NumberFormatException except) {
        System.out.println("ERROR: Integer expected instead of " + args[i]);
        return printUsage();
      } catch (ArrayIndexOutOfBoundsException except) {
        System.out.println("ERROR: Required parameter missing from " +
                           args[i-1]);
        return printUsage();
      }
    }
    // Make sure there are exactly 2 parameters left.
    if (other_args.size() != 2) {
      System.out.println("ERROR: Wrong number of parameters: " +
                         other_args.size() + " instead of 2.");
      return printUsage();
    }
    conf.setInputFormat(TextInputFormat.class);
    conf.setOutputFormat(TextOutputFormat.class);

    FileInputFormat.setInputPaths(conf, (String)other_args.get(0));
    FileOutputFormat.setOutputPath(conf, new Path((String)other_args.get(1)));


    //conf.set("mapred.job.tracker", "local");
    //conf.set("fs.default.name", "local");
    JobClient.runJob(conf);
    return 0;
  }


  public static void main(String[] args) throws Exception {
    int res = ToolRunner.run(new Configuration(), new WordCount3(), args);
    System.exit(res);
  }
}

